Comment: Gee wiz, I wonder what the outcome will be!!! I nominate Lord Hutton as Chairman! Independent? GIVE ME A BREAK.

President George W Bush bowed to mounting pressure yesterday and agreed to set up an independent inquiry into the shortcomings of the intelligence used to make the case for war in Iraq.

His decision leaves Tony Blair isolated in his claims that the intelligence assessments were accurate. It will increase pressure on him to order an inquiry into the reliability of British intelligence before the war.

Mr Bush had been resisting calls for an investigation while the hunt for weapons of mass destruction continued in Iraq.

But there has been a growing clamour for an inquiry since David Kay, America's chief weapons inspector, resigned 10 days ago saying that no stockpiles would be found and that the pre-war intelligence on Iraq was "almost all wrong".

The Tories will table a Commons motion calling for an inquiry and MPs are likely to be able to vote on it on Feb 11, the next day for an Opposition inspired debate.

Sir Menzies Campbell, the Liberal Democrats' foreign affairs spokesman, said: "This will put yet more pressure on the Government. Washington is now dictating the British political agenda. The Government's satisfaction at the Hutton report may well be shortlived."

Downing Street said: "We have been in close discussion with the US government in the last few days but we will not comment further until an official statement is made by the US."

The Government has repeatedly refused demands for an inquiry and ministers did so again yesterday. But Mr Blair, in a concession to his critics and in response to Mr Bush's admission that America might not have known all the "facts" about Iraq's WMD before it went to war, is expected to admit this week to doubts about finding WMD.

Mr Bush will sign an executive order this week to set up an independent commission to examine the differences between what America thought it had established before the war and what is now known.

With Democratic presidential contenders seizing on the issue to attack the White House, Republican congressmen have joined Democrats in calling for an inquiry into the use of and compilation of the intelligence that fuelled fears of Iraq's weapons.

"I don't see there is any way around it," said Sen Chuck Hagel, a senior Republican member of the Senate foreign relations committee. "We need to open this up in a very non-partisan, outside commission to see where we are."

The issue was not only the shortcomings of US intelligence but "the credibility of who we are around the world and the trust of our government and our leaders".

Sen Trent Lott of Mississippi, another senior Republican on the committee, said: "I think we have major problems with our intelligence community. We need to take a look at a complete overhaul."

There is to be no deadline for the inquiry's conclusions, which could cause great controversy in the approach to the presidential election in November.

Mr Kay welcomed the reports of Mr Bush's change of heart, first leaked in the Washington Post.

"When you make mistakes, you need to be seen as understanding why you made those mistakes," he said. "So in the next security crisis - Iran, Syria, wherever - they understand why we are concerned.

"If you cannot rely on accurate intelligence that is credible to the American people and others abroad, you can't have a policy of pre-emption."

The inquiry was not "a witch-hunt", Mr Kay said. "This is a way of looking into the fundamental flaws in collecting intelligence."

Paul Wolfowitz, the deputy defence secretary, one of the architects of the plan to overthrow Saddam Hussein, conceded that the intelligence might have been wrong but said the war was right.

"You have to make decisions based on the intelligence you have, not on the intelligence you can discover later," he said yesterday.

The White House's senior press official said the inquiry would be on the lines of the Warren Commission, named after Earl Warren, a former chief justice of the Supreme Court. He led a 10-month investigation that concluded in 1964 that Lee Harvey Oswald acted alone in killing President John F Kennedy.

The official said that Mr Bush would appoint the members of the commission but insisted that the investigation would be independent.

Tomorrow the Prime Minister gives evidence to the Commons liaison committee, a group of select committee chairmen, when he is expected to "give some ground" on the question of whether WMD will be found.

Michael Howard, the Conservative leader, said in an interview with The Telegraph that he wanted an inquiry because it was "of the utmost importance" to find out what went wrong with the intelligence before the attack on Saddam's regime.